Credit: Atomic Energy Commission
April 19 is Glenn T. Seaborg’s birthday. Seaborg was an American chemist who discovered ten of the transuranium elements and over 100 different isotopes. Seaborg also proposed the actinide group arrangement for the periodic table.
These elements were plutonium, americium, curium, berkelium, californium, einsteinium, fermium, mendelevium, nobelium and element 106. Element 106 was named seaborgium in 1997 in his honor. He shares the 1951 Nobel Prize in Chemistry with Edwin McMillan for these discoveries.
These elements were all created at the University of California, Berkeley’s radiation laboratory. They accelerated protons, alpha particles (helium nuclei) and element nuclei with their cyclotron at various high atomic number targets in the hope of these particles being forced into the nucleus of the target. This technique is the basis for creating the elements found at the upper end of the periodic table.
He was a frequent advisor to Presidents from Truman to Clinton on topics of nuclear energy. He advocated arms control treaties such as the Limited Test Ban Treaty and Nuclear Non-Proliferation Treaty. He also pushed for peaceful applications of nuclear energy such as power plants. He served as head of the Atomic Energy Commission from 1961 – 1971.
Fun fact: Seaborg is the only person to ever obtain a patent for an element. In fact, he was granted two patents for the elements: curium and americium.
Notable Science History Events for April 19
2013 – François Jacob died.
Jacob was a French biologist who with Jacques Monod, came up with the idea of enzyme levels in cells are controlled and regulated through transcription of DNA. They performed studies of E. coli bacteria in lactose broth. The E. coli needs glucose to survive and managed to adapt itself to break lactose into glucose and galactose. It went further to convert the galactose into glucose. They found there were specific proteins preventing the transcription of DNA. This would express itself as the specific proteins are needed due to the environment of the bacteria.
This research would earn the two men half the 1965 Nobel Prize in Medicine.
1975 – First Indian satellite launched.
India successfully launched their Aryabhata satellite using a Soviet Intercosmos rocket into orbit.
India entered an agreement with the Soviet Union to exchange the use of Indian ports for the use of Soviet rockets to launch their satellites. India’s first satellite was designed to test their tracking systems and conduct x-ray and solar astronomy experiments. It consisted of a 2.4 m diameter 26-sided polyhedron covered in solar cells. In spite of all these solar cells, the satellite lost power after four days and experiments ended abruptly at the 5-day mark. The satellite itself managed to stay in orbit until February 1992.
Fun fact: The name of this satellite Aryabhata is the same name of the famous 5th Century Indian mathematician and astronomer. His Aryabhatiya textbook covered topics of algebra, plane, and spherical trigonometry, quadratics, and trigonometrical tables and exists to this day.
1975 – Percy Lavon Julian died.
Julian was an African-American chemist and pioneer of steroid synthesis from plant sources. He was the first to synthesize the steroid physostigmine used for the treatment of glaucoma. He also discovered an industrial process to make the precursor steroid stigmasterol from soybean oil which created a new branch of pharmaceutical development.
Find out more about Percy Lavon Julian on April 11 in Science History.
1971 – First space station launched.
The Soviet space agency launched the Salyut 1 space station into orbit. It was the first space station able to house astronauts to perform experiments in space. The station was comprised of three pressurized modules with 90 m3 volume of living space. The Orion 1 Ultraviolet Observatory was installed onboard to become the first observatory in space.
There were two missions planned to man the Salyut station but the first had a malfunction in their autodocking systems and had to be aborted. The second mission docked successfully but had to be cut short after 23 days when a series of problems cumulated in an electrical fire. The crew escaped in their capsule and landed in Kazakhstan. When the recovery crew arrived, they found all three cosmonauts dead in their couches. The investigation showed a valve opened the capsule to space as it re-entered the atmosphere.
The Soviet space program attempted to push through redesigns to the Soyuz capsules to make redocking more efficient and allow spacesuits to be worn during operations. Before this could be completed, Salyut 1 was having problems. It was running out of propellant to keep it in orbit. The decision was made to have Salyut re-enter the atmosphere intentionally. It re-entered the atmosphere after 175 days in orbit.
1912 – Glenn T. Seaborg was born.
1906 – Pierre Curie died.
Pierre Curie and his wife Marie shared half the 1903 Nobel Prize in Physics for their research into radiation. They also discovered the elements radium and polonium.
He also co-discovered the piezoelectric effect with his brother Jacques where compressed crystals give off an electric field. This discovery is mostly exploited by crystal oscillators in clocks and other scientific instruments for calibration.
Pierre is the Curie responsible for the magnetism law known as Curie’s Law. This law relates temperature of a material and its magnetic properties. As temperatures increase, a material loses its magnetic properties until at a certain point (known as the Curie Point) the material exhibits no magnetic properties.
Curie died as he was crossing a street in the rain. He slipped and fell under a horse-drawn cart where he fractured his skull.
1882 – Charles Darwin died.
Darwin is best known for his two works “On the Origin of Species” and “Descent of Man” outlining his theories of evolution and his voyages to the Galapagos Islands aboard the H.M.S. Beagle.
He outlined how all species of life branch from other species through a process he called natural selection. Natural selection was how a species pass on survival properties by successfully surviving to reproduce. If a mutation occurs that improves survivability, this mutation could be passed on to their offspring. Unsuccessful species die off before reproducing and therefore, do not pass on the bad mutation.